Geologic units in Johnson county, Texas

Woodbine Formation (Late Cretaceous; Gulfian Series) at surface, covers 26 % of this area

Woodbine Formation

Undivided part of Washita Group (Early Cretaceous; Comanchean Series) at surface, covers 25 % of this area

Undivided part of Washita Group

Eagle Ford Formation (Late Cretaceous) at surface, covers 19 % of this area

Eagle Ford Formation

Grayson Marl and Main Street Limestone, undivided (Early Late Cretaceous and Late Early Cretaceous) at surface, covers 17 % of this area

Grayson Marl and Main Street Limestone, undivided

Undivided part Fredericksberg Group (Early Cretaceous) at surface, covers 6 % of this area

Undivided part Fredericksberg Group

Walnut Clay (Early Cretaceous) at surface, covers 2 % of this area

Walnut Clay

Terrace deposits (Pleistocene and Holocene) at surface, covers 2 % of this area

Terrace deposits

Alluvium (Holocene) at surface, covers 2 % of this area

Alluvium

Quaternary deposit, undivided (Quaternary) at surface, covers 0.6 % of this area

Quaternary deposit, undivided

Paluxy Sand (Early Cretaceous) at surface, covers 0.5 % of this area

Paluxy Sand

Kiamichi Formation (Early Cretaceous; Comanchean Series) at surface, covers 0.5 % of this area

Kiamichi Formation

Duck Creek Limestone (Early Cretaceous; Comanchean Series) at surface, covers 0.2 % of this area

Duck Creek Limestone

Goodland Limestone and Walnut Clay, undivided (Early Cretaceous; Comanchean Series) at surface, covers < 0.1 % of this area

Goodland Limestone and Walnut Clay, undivided

Glen Rose Limestone (Early Cretaceous) at surface, covers < 0.1 % of this area

Glen Rose Limestone